From f12ac5b77612c9dbdbbf7f34cfda4a96d5cdc732 Mon Sep 17 00:00:00 2001
From: Evgeniy Stepanov <eugeni.stepanov@gmail.com>
Date: Mon, 22 May 2017 21:11:44 +0000
Subject: [PATCH] [lld] Infer relocation model from module flags in relocatable
 LTO link.

Fix for PR33096.

llvm-svn: 303579
---
 lld/ELF/LTO.cpp                                 |  7 +++-
 lld/test/ELF/lto/Inputs/relocation-model-pic.ll | 11 ++++++
 lld/test/ELF/lto/relocation-model.ll            | 46 +++++++++++++++++++++++++
 3 files changed, 63 insertions(+), 1 deletion(-)
 create mode 100644 lld/test/ELF/lto/Inputs/relocation-model-pic.ll
 create mode 100644 lld/test/ELF/lto/relocation-model.ll

diff --git a/lld/ELF/LTO.cpp b/lld/ELF/LTO.cpp
index dd43517..6915d97 100644
--- a/lld/ELF/LTO.cpp
+++ b/lld/ELF/LTO.cpp
@@ -73,7 +73,12 @@ static std::unique_ptr<lto::LTO> createLTO() {
   Conf.Options = InitTargetOptionsFromCodeGenFlags();
   Conf.Options.RelaxELFRelocations = true;
 
-  Conf.RelocModel = Config->Pic ? Reloc::PIC_ : Reloc::Static;
+  if (Config->Relocatable)
+    Conf.RelocModel = None;
+  else if (Config->Pic)
+    Conf.RelocModel = Reloc::PIC_;
+  else
+    Conf.RelocModel = Reloc::Static;
   Conf.CodeModel = GetCodeModelFromCMModel();
   Conf.DisableVerify = Config->DisableVerify;
   Conf.DiagHandler = diagnosticHandler;
diff --git a/lld/test/ELF/lto/Inputs/relocation-model-pic.ll b/lld/test/ELF/lto/Inputs/relocation-model-pic.ll
new file mode 100644
index 0000000..e766054
--- /dev/null
+++ b/lld/test/ELF/lto/Inputs/relocation-model-pic.ll
@@ -0,0 +1,11 @@
+target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
+target triple = "x86_64-unknown-linux-gnu"
+
+@foo = external global i32
+define i32 @main() {
+  %t = load i32, i32* @foo
+  ret i32 %t
+}
+
+!llvm.module.flags = !{!0}
+!0 = !{i32 1, !"PIC Level", i32 2}
diff --git a/lld/test/ELF/lto/relocation-model.ll b/lld/test/ELF/lto/relocation-model.ll
new file mode 100644
index 0000000..78334dd
--- /dev/null
+++ b/lld/test/ELF/lto/relocation-model.ll
@@ -0,0 +1,46 @@
+; REQUIRES: x86
+
+; RUN: llvm-as %s -o %t.o
+; RUN: llvm-as %p/Inputs/relocation-model-pic.ll -o %t.pic.o
+
+;; Non-PIC source.
+
+; RUN: ld.lld %t.o -o %t-out -save-temps -shared
+; RUN: llvm-readobj -r %t-out.lto.o | FileCheck %s --check-prefix=PIC
+
+; RUN: ld.lld %t.o -o %t-out -save-temps --export-dynamic --noinhibit-exec -pie
+; RUN: llvm-readobj -r %t-out.lto.o | FileCheck %s --check-prefix=PIC
+
+; RUN: ld.lld %t.o -o %t-out -save-temps --export-dynamic --noinhibit-exec
+; RUN: llvm-readobj -r %t-out.lto.o | FileCheck %s --check-prefix=STATIC
+
+; RUN: ld.lld %t.o -o %t-out -save-temps -r --export-dynamic
+; RUN: llvm-readobj -r %t-out.lto.o | FileCheck %s --check-prefix=STATIC
+
+
+;; PIC source.
+
+; RUN: ld.lld %t.pic.o -o %t-out -save-temps -shared
+; RUN: llvm-readobj -r %t-out.lto.o | FileCheck %s --check-prefix=PIC
+
+; RUN: ld.lld %t.pic.o -o %t-out -save-temps --export-dynamic --noinhibit-exec -pie
+; RUN: llvm-readobj -r %t-out.lto.o | FileCheck %s --check-prefix=PIC
+
+; RUN: ld.lld %t.pic.o -o %t-out -save-temps --export-dynamic --noinhibit-exec
+; RUN: llvm-readobj -r %t-out.lto.o | FileCheck %s --check-prefix=STATIC
+
+; RUN: ld.lld %t.pic.o -o %t-out -save-temps -r --export-dynamic
+; RUN: llvm-readobj -r %t-out.lto.o | FileCheck %s --check-prefix=PIC
+
+
+; PIC: R_X86_64_REX_GOTPCRELX foo
+; STATIC: R_X86_64_PC32 foo
+
+target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
+target triple = "x86_64-unknown-linux-gnu"
+
+@foo = external global i32
+define i32 @main() {
+  %t = load i32, i32* @foo
+  ret i32 %t
+}
-- 
2.7.4